Time-Modulated Ultra-Wideband Multichannel Data System

The key innovation of this proposal is implementation of a Time Modulated Ultra-wideband (TM-UWB) radio to implement a bi-directional astronaut to spacecraft wireless link. Our innovation will also provide a real-time reading of the position of the astronaut, and with two small conformal antennas on the astronaut, it will provide the astronaut orientation and position in real-time. Within the last few years low cost ultra-high precision oscillators have become available, and these now make it possible to build TM-UWB communication systems which have no base band frequency. The only signals transmitted are pulses which can be generated by a single transistor which is either on or off. Impulses in the time domain generate very wide bandwidth signals in the frequency domain, and the signals generated by our current hardware have bandwidths in the several gigahertz range. With TM-UWB transmission, there is little chance of multipath interference, and the transmission is inherently secure since if you don't know the specific pseudo-random pulse pattern being used, the transmission is well below the noise in any detectable frequency range. Since the duty cycle of pulse transmission is small (.001), average power consumption is very small compared to radios which transmit continuously at some baseband frequency.